Steinberg told USA TODAY Sports the NFL will announce the suspension on Monday.

Steinberg said Prater had been in the NFL's substance abuse program since a drunken driving arrest in suburban Denver in Aug. 2011, and was prohibited from drinking alcohol, a common stipulation for players with DUI arrests. Steinberg said Prater tested positive for alcohol this summer after drinking beer at his home, while on vacation.

"This guy was off probation. There's no allegation that he used PEDs or illegal drugs," Steinberg said. "He was on vacation, had three beers three years after a DUI. Come on, give me break."

The 2011 arrest came within days of the end of the NFL lockout, and Prater – who at the time was a restricted free agent – was not allowed to practice with the team because of the NFL's post-lockout rules.

That was Prater's second DUI while with the Broncos. According to records from the Florida Department of Law Enforcement obtained by USA TODAY Sports, Prater was charged with DUI in Orlando January 2008, about a month after he was signed by the Broncos. Court records show Prater pleaded no contest to that charge and was sentenced to one year probation, 50 hours of community service and had his license suspended for six months. Prater completed probation in 2009, and was not in the NFL's drug program at the time of his arrest in 2011, Steinberg said.

Prater's impending suspension is his first punishment from the league.

"They said they won't take punitive action for things that occurred during the lockout, but we can put you in the [substance abuse] program," Steinberg said.

Steinberg said he and the NFL had negotiated Prater's punishment down to four games from a year's ban – the punishment for a violation for a player in stage three of the drug program. The punishment was finalized before Denver's third preseason game Saturday night against Houston. He made a 32-yard field goal and one extra point in that game.

Prater broke the NFL record when he kicked a 64-yard field goal last year in a December game against Tennessee. He is consistently one of the NFL's best long-range kickers, and his biggest value to the Broncos is on kickoffs, particularly in Denver where he makes nearly ever kick unreturnable.

The Broncos signed rookie Mitch Ewald this offseason. He missed a field goal Saturday night and is not the touchback weapon Prater is. The Broncos could sign a veteran kicker if one becomes available in coming weeks.

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